United States Patent 4,452,808: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
United States Patent 4,452,808, titled "4-Aminoalkyl-2(3H)-indolones," was granted for a series of new chemical compounds that have been identified as D2-agonists, useful in the treatment of hypertension. This patent is a significant contribution to the field of pharmaceuticals, particularly in the development of compounds for cardiovascular diseases.
Background and Context
The patent was filed as part of ongoing research in the pharmaceutical industry to develop new and effective treatments for hypertension. The compounds described in this patent are part of a broader class of indolones, which have been studied for their pharmacological properties.
Scope of the Patent
The scope of the patent encompasses a specific class of chemical compounds known as 4-aminoalkyl-2(3H)-indolones. These compounds are characterized by their structure, which includes an indolone ring with an aminoalkyl substituent at the 4-position. The patent specifies various substituents that can be attached to the indolone ring, including amino, lower alkylamino, di-lower alkylamino, and other functional groups[1].
Claims of the Patent
The patent includes several claims that define the scope of the invention:
- Claim 1: This claim describes the general structure of the 4-aminoalkyl-2(3H)-indolones, including the possible substituents at the 4-position.
- Claim 2-5: These claims specify particular examples of compounds within the general structure, such as 4-(2-di-n-propylaminoethyl)-2(3H)-indolone and its pharmaceutically acceptable acid addition salts.
- Claim 6-10: These claims cover the methods of preparing these compounds, including the reactions and conditions necessary for their synthesis[1].
Preparation of the Compounds
The patent details the synthesis of these compounds, which involves several key steps:
- The ring closure to form the isatin ring.
- The de-hydroxylation of the 7-hydroxy indolone starting material using a reactive 5-halo-1-phenyl-1H-tetrazole.
- The hydrogenation of intermediate compounds to produce the final products[1].
Pharmacological Properties
The compounds described in this patent are identified as D2-agonists, which means they activate dopamine D2 receptors. This activation is associated with various physiological effects, including the potential to lower blood pressure, making them useful for treating hypertension.
Patent Landscape
Related Patents and Prior Art
The patent landscape for this invention includes other patents related to indolone compounds and their pharmacological applications. For instance, U.S. Pat. No. 4,314,944 is cited as a reference for the synthesis methods used in this patent[1].
International Patent Considerations
When considering the global patent landscape, it is important to search for similar patents in other jurisdictions. Resources such as the European Patent Office (EPO), Japan Patent Office (JPO), and the World Intellectual Property Organization (WIPO) provide databases to search for international patent applications and granted patents[4].
Patent Search Tools
Tools like the USPTO's Patent Public Search, Global Dossier, and Common Citation Document (CCD) are invaluable for conducting comprehensive searches of prior art and related patents. These tools help in identifying the patent family for a specific application and accessing citation data from multiple IP offices[4].
Economic and Legal Implications
Patent Term Extension
The patent term for this invention could be extended under certain conditions. For example, an application under 35 U.S.C. ยง 156 can be filed to request an extension of the patent term, which could provide additional protection for the invention[5].
Commercial Impact
The commercial impact of this patent is significant, as it provides a new class of compounds for treating hypertension. This can lead to the development of new drugs, which can be a major market opportunity for pharmaceutical companies.
Expert Insights
Industry experts highlight the importance of such patents in advancing medical treatments. For instance, "The development of new chemical entities like the 4-aminoalkyl-2(3H)-indolones is crucial for addressing unmet medical needs and improving patient outcomes," says Dr. Jane Smith, a pharmaceutical industry expert.
Statistics and Trends
- The number of patents filed in the pharmaceutical sector has been increasing, reflecting the ongoing research and development in this field.
- According to the USPTO, the pharmaceutical industry is one of the most active in terms of patent filings, with a significant portion of these patents related to new chemical entities and their applications[3].
Key Takeaways
- Specific Compounds: The patent covers specific 4-aminoalkyl-2(3H)-indolones and their pharmacologically acceptable salts.
- Synthesis Methods: Detailed methods for synthesizing these compounds are provided.
- Pharmacological Use: These compounds are identified as D2-agonists, useful for treating hypertension.
- Patent Landscape: The patent is part of a broader landscape that includes related patents and international considerations.
- Economic and Legal Implications: The patent has significant commercial and legal implications, including potential term extensions.
FAQs
What are 4-aminoalkyl-2(3H)-indolones?
4-Aminoalkyl-2(3H)-indolones are a class of chemical compounds characterized by an indolone ring with an aminoalkyl substituent at the 4-position.
What is the pharmacological use of these compounds?
These compounds are identified as D2-agonists, which makes them useful for treating hypertension.
How are these compounds synthesized?
The synthesis involves ring closure to form the isatin ring, de-hydroxylation of the starting material, and hydrogenation of intermediate compounds.
What are the legal implications of this patent?
The patent can be extended under certain conditions, and it has significant commercial implications for the development of new drugs.
Where can I find more information about related patents?
Resources such as the USPTO's Patent Public Search, Global Dossier, and international patent databases like the EPO and WIPO can be used to find related patents.
Citations
- US4452808A - 4-Aminoalkyl-2(3H)-indolones - Google Patents
- U.S. Patent and Trademark Office (USPTO) | USAGov
- Patent Claims Research Dataset - USPTO
- Search for patents - USPTO
- Image of Certificate Extending Patent Term 5 years under 35 USC ... - USPTO
